Structural Determination of Apolipoprotein A-I/preb-HDL Particles
EMSL Project ID
10593
Abstract
Apolipoprotein A-I (apoAI) is a 243-residue exchangeable apolipoprotein that plays a key role in the high-density lipoprotein (HDL) pathway, which clears the "bad cholesterol" from human blood stream. ApoAI is the most abundant protein component in HDL (~70%). Depending on the extent of lipidation, apoAI displays a dramatic conformational plasticity and may adopt one of four distinct conformations: (1). Lipid-free apoAI, (2). ApoAI/prebHDL, (3). ApoAI/DIscHDL, (4). ApoAI/sphericalHDL. Importantly, each conformation mediates one specific biological function, which regulates HDL formation, maturation and transportation. We plan to solve one of the apoAI conformation: apoAI on the prebHDL. Previously, using our 500 MHz and PNNL's high-field NMR instruments, we collected high quality 3D-NMR data set, allowing us to achieve ~85% backbone assignment of this 243-residue protein (MW of prebetaHDL: 55 kDa). We will also collect two 4D-NMR spectral in August. In this proposal, we request more high-field NMR data so that we can finish two other 4D-NMR experiments. These are a set of 4D NMR experiments used for spectral assignment with significant spectral overlap. We anticipate that these 4D-NMR experiments will allow us to completely assign the backbone atoms. We also request 600 MHz NMR time (with a cold probe) for a 3D 15N/13C-filtered NOESY for measurement of apoAI/POPC interaction. These NMR experiments will allow us to solve the structure of apoAI/prebHDL particles.
Project Details
Project type
Capability Research
Start Date
2004-10-20
End Date
2005-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members